+/*
+ * "Copyright (c) 2008, 2009 The Regents of the University of California.
+ * All rights reserved."
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose, without fee, and without written agreement is
+ * hereby granted, provided that the above copyright notice, the following
+ * two paragraphs and the author appear in all copies of this software.
+ *
+ * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
+ * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
+ * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS."
+ *
+ */
#include <stdio.h>
#include <stdint.h>
-// #include <assert.h>
#include <string.h>
#include "tcplib.h"
struct circ_buf {
- uint8_t *map;
- uint16_t map_len;
uint8_t *data_start;
uint8_t *data_head;
uint16_t data_len;
uint32_t head_seqno;
};
-int circ_buf_init(void *data, int len, uint32_t seqno, int incl_map) {
+int circ_buf_init(void *data, int len, uint32_t seqno) {
struct circ_buf *b = (struct circ_buf *)data;
- int bitmap_len = ((len - sizeof(struct circ_buf)) / 9);
- // int data_len = bitmap_len * 8;
-
- // printf("circ_buf_init: len: %i data_len: %i bitmap_len: %i\n", len, data_len, bitmap_len);
- // assert(bitmap_len + data_len + sizeof(struct circ_buf) <= len);
if (len < sizeof(struct circ_buf))
return -1;
- if (incl_map) {
- b->map = (uint8_t *)(b + 1);
- b->map_len = bitmap_len;
- b->data_start = b->map + bitmap_len;
- b->data_len= bitmap_len * 8;
- memset(b->map, 0, bitmap_len * 9);
- } else {
- b->map = NULL;
- b->map_len = 0;
- b->data_start = (uint8_t *)(b + 1);
- b->data_len = len - sizeof(struct circ_buf);
- memset(b->data_start, 0, b->data_len);
- }
- b->data_head = b->data_start;
+ b->data_head = b->data_start = (uint8_t *)(b + 1);
+ b->data_len = len - sizeof(struct circ_buf);
b->head_seqno = seqno;
-
- // printf("circ_buf_init: buf: %p data_start: %p data_head: %p data_len: %i\n",
- // b, b->data_start, b->data_head, b->data_len);
-
return 0;
}
-#define BIT_SET(off,map) map[(off)/8] |= (1 << (7 - ((off) % 8)))
-#define BIT_UNSET(off,map) map[(off)/8] &= ~(1 << (7 - ((off) % 8)))
-#define BIT_ISSET(off, map) map[(off)/8] & 1 << (7 - (off) % 8)
-
-static void bitmap_mark(struct circ_buf *b, uint8_t *data, int len) {
- int offset = data - b->data_start;
- if (b->map_len == 0) return;
- while (len-- > 0) {
- BIT_SET(offset, b->map);
- offset = (offset + 1) % b->data_len;
- }
-}
-
-/* return the sequence number of the first byte of data in the buffer;
- this is what the stack can ACK. */
uint32_t circ_get_seqno(void *buf) {
struct circ_buf *b = (struct circ_buf *)buf;
return b->head_seqno;
}
-void circ_set_seqno(void *buf, uint32_t seqno) {
- struct circ_buf *b = (struct circ_buf *)buf;
- b->head_seqno = seqno;
-}
-
-uint16_t circ_get_window(void *buf) {
- struct circ_buf *b = (struct circ_buf *)buf;
- return b->data_len;
-}
-
-/* read as many contiguous bytes from the head of the buffer as
- * possible, and update the internal data structures to shorten the
- * buffer
- *
- * buf: the circular buffer
- * data: a pointer which will be updated with the location of the data
- * return: the number of bytes available
- */
-int circ_buf_read_head(void *buf, char **data) {
- struct circ_buf *b = (struct circ_buf *)buf;
- int off = b->data_head - b->data_start;
- int rlen = 0;
- *data = b->data_head;
- while (BIT_ISSET(off, b->map) && off < b->data_len) {
- BIT_UNSET(off, b->map);
- rlen++;
- b->head_seqno++;
- b->data_head ++;
- if (b->data_head == b->data_start + b->data_len)
- b->data_head = b->data_start;
- off++;
- }
- return rlen;
-}
-
-
static void get_ptr_off_1(struct circ_buf *b, uint32_t sseqno, int len,
uint8_t **writeptr, int *w_len) {
uint8_t *endptr = b->data_start + b->data_len;
int offset;
*writeptr = NULL;
- *w_len = 0;
+ *w_len = len;
/* write up to either the end of the buffer */
offset = sseqno - b->head_seqno;
if (b->data_head + offset < endptr) {
- *w_len = len;
*writeptr = b->data_head + offset;
- if (*writeptr + *w_len > endptr) {
- *w_len = endptr - *writeptr;
- }
+ } else {
+ offset -= (endptr - b->data_head);
+ *writeptr = b->data_start + offset;
+ }
+ if (*writeptr + *w_len > endptr) {
+ *w_len = endptr - *writeptr;
}
}
int offset = seqno - b->head_seqno;
b->head_seqno = seqno;
-
b->data_head += offset;
+
while (b->data_head > b->data_start + b->data_len)
b->data_head -= b->data_len;
return rc;
}
-int circ_buf_write(void *buf, uint32_t sseqno,
+int circ_buf_write(char *buf, uint32_t sseqno,
uint8_t *data, int len) {
struct circ_buf *b = (struct circ_buf *)buf;
uint8_t *writeptr;
int w_len;
-
/* we can't write any bytes since we're trying to write too far
ahead */
- // printf("circ_buf_write: sseqno: %i head_seqno: %i len: %i\n",
- // sseqno, b->head_seqno, len);
-
if (sseqno > b->head_seqno + b->data_len)
return -1;
-
- if (sseqno < b->head_seqno) {
- /* old data, but already received */
- if (sseqno < b->head_seqno - len) return -1;
- /* a segment which overlaps with data we've already received */
- data += (b->head_seqno - sseqno);
- len -= (b->head_seqno - sseqno);
- sseqno = b->head_seqno;
- }
if (len == 0) return 0;
- // printf("circ_buf_write: buf: %p data_start: %p data_head: %p data_len: %i\n",
- // b, b->data_start, b->data_head, b->data_len);
get_ptr_off_1(b, sseqno, len, &writeptr, &w_len);
+
memcpy(writeptr, data, w_len);
data += w_len;
- bitmap_mark(b, writeptr, w_len);
if (w_len != len) {
writeptr = b->data_start;
w_len = min(len - w_len, b->data_head - b->data_start);
memcpy(writeptr, data, w_len);
- bitmap_mark(b, writeptr, w_len);
- // printf("circ_buf_write (2): write: %p len: %i\n", writeptr, w_len);
}
+
return 0;
}
#ifdef PC
void circ_buf_dump(void *buf) {
struct circ_buf *b = (struct circ_buf *)buf;
+ uint8_t *d;
int i;
/* printf("circ buf: %p\n\tmap: %p\n\tmap_len: %i\n\tdata_start: %p\n\t" */
/* "data_head: %p\n\tdata_len: %i\n\thead_seqno: %i\n", */
/* b, b->map, */
/* b->map_len, b->data_start, b->data_head, b->data_len, b->head_seqno); */
-
- for (i = 1; i <= b->data_len; i++) {
- if (BIT_ISSET(i-1, b->map))
- putc('x',stdout);
- else
- putc('_',stdout);
- if (i % 80 == 0 || i == b->data_len) {
- putc('\n',stdout);
- }
+ for (d = b->data_start; d < b->data_start + b->data_len; d++) {
+ if (d == b->data_head) putc('|', stdout);
+ printf("%2.x ", *d);
}
+ putc('\n', stdout);
}
#endif
projects / tinyos-2.x.git / blobdiff